Aerosol spray containers have been well known in the art for decades. A typical aerosol container utilizes an assembly to actuate and release the pressurized materials in the canister and direct them toward an intended target. Such prior art containers have often utilized a spray through overcap consisting of a one piece housing and actuator. These containers are usually operated by directly pressing the actuator down to engage a valve stem and thereby release the pressurized material from the canister. Although devices of this type have at times been adequate to permit material to be sprayed from a pressurized canister, they have exhibited a number of drawbacks. To begin with, the spray pattern associated with such containers was generally imprecise or inconsistent. Such devices frequently exhibited a broad cone spray pattern with excessive turbulence and eddy currents. Such spray patterns have proven to be particularly troublesome in aerosol products containing hazardous or potentially irritating chemicals, particularly when used in windy or confined environments. Use of these devices frequently resulted in the spraying or contamination of unintended targets including the user.
In order to attempt to improve the spray characteristics of aerosols, a nozzle insert has sometimes added into the actuator. While this generally improved the spray characteristics, it still left other issues. For example, although such inserts were capable of focusing the output in a narrow stream, they did not perform well to precisely produce desired spray patterns that combined the characteristics of cone and stream type patterns. The resultant spray patterns were often so narrow that they required multiple sprays or excessive movement to cover an intended target. Likewise the force of the resultant streams was at times sufficient to cause injury upon contact with delicate areas such as the eyes. Additionally, most actuator/insert constructions did not permit one to select or modify a spray pattern of a given actuator.
Most of the available overcaps for aerosol products operate to dispense products in the same manner. The overcaps use an actuator to engage an aerosol valve stem to pass the pressurized product into the actuator for dispensing. A portion of the bottom of the overcap is usually attached to the outside diameter of the aerosol valve and container to render it non-removable. The pressurized product is typically dispensed by pressing the actuator into engagement with the aerosol valve stem. Typically, a spring biasing force must be overcome by the actuator in order to engage and depress the valve stem and dispense the product. Since it is desired to allow the user to dispense an aerosol product without necessitating the use of excessive force, the biasing force that must be overcome by pressing the actuator, has generally been relatively minimal. While this condition was necessary for intended operation of the aerosol container, it likewise made the undesired effect of potential unintended actuation and dispensing just as easy. This was a particular problem for any aerosols that contain active ingredients that could cause some degree of harm or discomfort to the user or surroundings. As a result, significant efforts have been directed towards making accidental dispensing of aerosol containers more difficult to occur.
A typical way of attempting to prevent the accidental, or otherwise unintended, dispensing of aerosol products has been to add a locking mechanism to the overcap. Most such mechanisms provide an additional piece on the aerosol overcap that requires the user to move the piece into a disengaged position in order to dispense the aerosol. Many of these devices, however, are either inconveniently located, difficult to operate with one hand or are themselves, readily unintentionally moved into engagement. An example of such a locking mechanism is a sliding lever on the side of the housing. In use, however, such a locking mechanism is often covered by the user's palm or fingers when dispensing the product from the aerosol container. Such locking mechanisms frequently exhibit an additional drawback, in that once the actuator is in an unlocked position, it remains unlocked and makes the system available for unintentional operation. The mechanism does not lock automatically after dispensing, but instead requires the user to perform an additional intentional locking action to return the lever or the like to a position where it prohibits operation of the actuator.
Another type of known locking mechanism utilizes an actuator that rotates into engagement with a supporting portion of the housing to prevent the user from pressing the actuator except in certain pre-designated positions. Like the mechanism described above, however, once the actuator is rotated into engagement, it remains unlocked until the user performs an additional intentional locking action as such accidental dispensing is only partly prohibited and the user again must remember to relock the system to prohibit such circumstances after use. A further problem with these systems and the previously described lever locking mechanisms, is that there is still a significant chance that the device can reach a disengaged or unlocked position due to environmental or unintentional acts, rather than the intentional act of the user thereby freely permitting accidental dispensing of product from the aerosol.
Some locking mechanisms that have utilized a spring-loaded system to return the device to a locked condition after dispensing have also exhibited shortcomings. Such devices have often required two hands for operation. Those devices that permit some type of single-handed operation, usually required the user to see the locking device to operate them, thus rendering them useless, for example, in the case of darkness or engaging a potentially hostile person with a non-lethal incapacitating spray.
Another known type of overcap uses a trigger to actuate the aerosol valve to dispense the aerosol product. The trigger usually is a separate piece or more often a number of pieces that are added into the housing of the overcap. The trigger is generally contained in the housing by undercuts or the like. Because the trigger is added to the actuator system, it can be dislodged from the housing when dropped or struck making operation of the dispensing system impossible. Other known designs have used additional parts in the assembly to lock the trigger when not in use, thereby introducing additional complexity. Such designs have still not provided the combination of a self locking action once the actuator is released into a closed position, along with the advantages of an improved spray pattern and ease of operation with one hand. In addition, many of these mechanisms have had difficulty handling submergence in water, shock and extreme operating temperatures while providing quiet and consistent use.
In view of the above, it is apparent that there exists a need in the art for an improved aerosol spray delivery and dispensing method and apparatus that overcomes the problems and difficulties described. It is the purpose of this invention to fulfill the above described needs in the art, as well as other needs apparent to the skilled artisan from the following detailed description of this invention.